Heat-treating fabric



oct. 18, .W. H' SHIELDS HEATTREATING FABRIC 2 Sheets-Sheet l Filed July v22, 1946 Sil Patented Oct. 18, 1949 vUNITED sTATEs PATENT OFFICE 2,485,072 HEAT-TREATING FABRIC wenden H. shields, Grand Rapids, Mien.

Application July 22.1946, serial No. 685,300

1 Claim.

This invention relates to heat treating fabrics and more particularly to treating fabrics made of thermoplastic thread or yarn of which nylon is an example although the invention is operable upon any thermoplastic fabric.

The purpose of the invention is to make a fabric smooth after it hasbeen fabricated or in some cases to imprint a pattern therein. To perform the operation the fabric is pressed between smooth surfaces, or surfaces having the desired pattern and then heated to the point where it becomes plastic and allowed to cool while pressed between said surfaces.

I have found it expedient to roll the plastic about a shaft having a continuous sheet of paper interposed between the layers of fabricupon the roll and the heat is applied by means of a high frequency electric current passed through the roll but in order for the high frequency current to become active I have found it necessary to moisten the fabric.

To properly prepare the roll of combined fabric and paper in alternate layers and to moisten the fabric I have used such a machine as is shown in either of the patents to Harry A. Shields No. 1,926,457 or No. 1,954,496. After the vfabric and paper have been rolled and the fabric steamed in such a machine thus giving it the proper .moisture content it is subjected to a high frequency electric current until it becomes heated to the plastic point of the fabric after which it is allowed to cool.

The accompanying drawings illustrate the invention in which,

Fig. 1 is a perspective view of a roll of cloth and paper.

Fig. 2 is a diagrammatic illustration of one method of applying the electric current to the roll.

Fig. 3 is an end view of the roll.

Figs. 4 and 5 are plan views of blankets each having an electric conductor used to wrap around the roll to apply the electric current thereto, and,

Fig. 6 is a fragmentary cross section of the roll of combined fabric and paper.

Like numbers refer to like parts in the different figures in the drawings.

The shaft about which the fabric and paper are rolled is of metal so that it will form the central electric conductor. About the shaft I is rolled the fabric 2 and the paper 3 so that when the roll is completed it comprises alternate layers of fabric and paper. During the rolling operation the fabric is moistened to the desired extent as by steam in the said patented machines. It is desirable to roll the fabric with even tension.

When the roll is completed it is prepared to receive the highy frequency electric current in a manner so that the current will pass uniformly throughout its entire body. This may be done by connecting one'of the conductors 4 from the source of current to the central shaft I and by wrapping around the periphery of the roll a wire 5 in helical fashion so that it will extend the whole length'of the roll and this wire is connected to the other conductor 6 from the source of current. To improve the conductivity and dispersal of the current and balance the two elements to get maximum resistance, I have found it advantageous to insert strips of electric conducting material 'I lengthwise of the roll under the coil 5.

When so prepared the curren-Lis applied and in passing `through the roll the fabric becomes and paper tightly and heated and the treatment is continued until the entire roll of fabric is heated to a plastic state or higher than subsequent processing temperatures whereupon the fabric will become smooth or if the separating sheet has a pattern formed in it the fabric will assume the shape of the pattern.

After the roll of fabric has been raised to the temperature in which it becomes plastic the roll is disconnected from the source of electric current and while still rolled it is allowed to cool and after it has become cool it is unrolled and the fabric will be foundto have assumed a smooth nish or a pattern if such a pattern was provided in the separating sheet.

As an alternative for the conductor coil 5 illustrated in Fig. `2 the blankets of Figs. 4 and 5 may be used. These blankets may be wrapped around the roll and provided with suitable fastening means lsuch as straps II and buckles I2. 'I'hese blankets are provided with electric conductors I3 consisting of wires laid evenly over the entire surfaces.` The surface areas of the central conductor I and the peripheral conductor should be substantially the same and therefore the length of the conductor wire I3 yin the blankets is calculated with the respect to its surface to have substantially the same surface area as the cental conductor I. The rolls of cloth and paper conductor I3 attached to one of theconductors 6 from the source of the electric current.

The invention is dened in the appended claim and is to be considered comprehensive of all forms of structure coming within its scope.

I claim:

The method of treating thermoplastic fabric which comprises moistening a length of thermoplastic fabric, winding said fabric anda super.. posed length of surfacing material onto an electrical conducting core resulting in alternate layers of fabric and surfacing material, surrounding said roll with an electrical conductor, connecting said core and said surrounding conductor in a high frequency electric circuit whereby said high frequency current passes through said roll heating the same, maintaining said current until said roll has become heated to the plastic point of the fabric, and then disconnecting said current and allowing said roll to cool.

' WENDELL H. SHIELDS.

The following references are le of this patent:

UNITED STATES PATENTS Number Narne Date Gessner Jan. 18, 1910 Westbrook Dec. 10, 1912 Price Aug. 21, 1917 Bulngton Aug. 29, 1933 Shields Sept. 12, 1933 Peel et al June 1 8, 1940 Hart Nov. 25, 1941 Steinberger May 4, 1943 Wilson May 11, 1943 Crandell July 13, 1943 

